Electron microscopic studies of bacteriophage M13 DNA replication. [Escherichia coli]

Journal Article · Tue Nov 01 04:00:00 EST 1977 · J. Virol.; (United States)

OSTI ID:5265702

Allison, D P; Ganesan, A T; Olson, A C; Snyder, C M; Mitra, S

Intracellular forms of M13 phage DNA isolated after infection of Escherichia coli with wild-type phage have been studied by electron microscopy and ultracentrifugation. The data indicate the involvement of rolling-circle intermediates in single-stranded DNA synthesis. In addition to single-stranded, circular DNA, we observed covalently closed and nicked replicative-form (RF) DNAs, dimer RF DNAs, concatenated RF DNAs, RF DNAs with single-stranded tails (sigma, rolling circles), and, occasionally, RF DNAs with theta structures. The tails in sigma molecules are always single stranded and are never longer than the DNA from mature phage; the proportion of sigma to other RF molecules does not change significantly with time after infection. The origin of single-stranded DNA synthesis has been mapped by electron microscopy at a unique location on RF DNA by use of partial denaturation mapping and restriction endonuclease digestion. This location is between gene IV and gene II, and synthesis proceeds in a counterclockwise direction on the conventional genetic map.

• Research Organization: Oak Ridge National Lab., TN
• OSTI ID: 5265702
• Journal Information: J. Virol.; (United States), Journal Name: J. Virol.; (United States) Vol. 24:2; ISSN JOVIA
• Country of Publication: United States
• Language: English

Related Subjects

550200 -- Biochemistry
550400* -- Genetics
59 BASIC BIOLOGICAL SCIENCES
BACTERIA
BACTERIOPHAGES
BIOSYNTHESIS
CENTRIFUGATION
DNA
DNA REPLICATION
ELECTRON MICROSCOPY
ESCHERICHIA COLI
GENES
GENETIC MAPPING
MICROORGANISMS
MICROSCOPY
NUCLEIC ACID REPLICATION
NUCLEIC ACIDS
ORGANIC COMPOUNDS
PARASITES
SEPARATION PROCESSES
SYNTHESIS
ULTRACENTRIFUGATION
VIRUSES